The 10ZiG RBT616 has a standard Phoenix AwardBIOS. Hit the DEL key on power-up to enter the setup screens.
If you find that a password is set the default password is 10ZIG.
At the top of the list in the Advanced BIOS Features screen you'll find an entry for Hard Disk Boot Priority [Press Enter]. Press Enter. With no USB pen drive present the following screen will just show the internal flash memory - in my case identified as:
1. Ch0 M. : CSS HAH40-002G
If you have a pen drive present it should appear in this list. For example,
with a 4GB Windows 10 installation pen drive plugged in I get:
1. USB-HDD0 : San Disk Cruzer Blade 2. Ch0 M. : CSS HAH40-002G
If your pen drive doesn't appear check the BIOS screen Integrated Peripherals. Ensure that all the USB options are set to Enabled. If they were previously set to Disabled it might be a good idea to save the settings and reboot before continuing.
At the bottom of the screen is an entry labelled:
*** USB Mass Storage Device Boot Setting ***
If you have a pen drive inserted it should be listed here. I set the option to Auto. It can be set to FDD (boot as if it is a floppy disk) or HDD (boot as if it is a hard disk).
As far as I can see the pen drive does not have to be bootable to appear in this list. If it doesn't appear then there may be some incompatibility between your chosen pen drive and the thin client.
Returning to the Advanced BIOS Features screen you can set the options for the First and Second Boot Device. The options are:
When using a pen drive this should be set to [Hard Disk] with the pen drive/flash priority being set in the hard Disk Boot Priority entry at the top of the list.
RBT-616V runs Windows Embedded Standard (XPe sp3 2009).